![DL7MAJ Stefan](/img/default-banner.jpg)
- 201
- 302 083
DL7MAJ Stefan
Germany
Registrace 28. 07. 2018
Amateur Radio Station DL7MAJ, Munich / Germany
I´m a retired engineer and from time to time i´ll show here some topics regarding repair/restauration or basics in the field of electronics, amateur radio, measurement equipment and so on. It´s just a hobby for me - i don´t earn money with it and i have no commercial interests (no clickbaiting). So simply have fun watching my videos - or not.... it´s up to you!
PLEASE NOTE 1: High voltages may be lethal! Do any work on electrical equipment only if you are trained and experienced!
PLEASE NOTE 2: My time for personal advice or repair support is limited; i don´t have much time for it. This is no commercial repair shop, maybe i can help you from time to time, but it´s up to me whether i accept any jobs or not!
I try to read all e-Mails and comments and try to give a short answer if possible, but please don't be offended if I don't reply or if i refuse to give any support.
I´m a retired engineer and from time to time i´ll show here some topics regarding repair/restauration or basics in the field of electronics, amateur radio, measurement equipment and so on. It´s just a hobby for me - i don´t earn money with it and i have no commercial interests (no clickbaiting). So simply have fun watching my videos - or not.... it´s up to you!
PLEASE NOTE 1: High voltages may be lethal! Do any work on electrical equipment only if you are trained and experienced!
PLEASE NOTE 2: My time for personal advice or repair support is limited; i don´t have much time for it. This is no commercial repair shop, maybe i can help you from time to time, but it´s up to me whether i accept any jobs or not!
I try to read all e-Mails and comments and try to give a short answer if possible, but please don't be offended if I don't reply or if i refuse to give any support.
#201 YAESU SOMMERKAMP FT221 Part 8
Searching for a faulty uA703 and - surprise - it isn´t the uA703!
zhlédnutí: 513
Video
#200 YAESU SOMMERKAMP FT221 Part 7
zhlédnutí 391Před 2 měsíci
It is Groundhog Day - see and be amused - i´m not amused of course ... hi
#199 YAESU SOMMERKAMP FT 221 Part 6
zhlédnutí 572Před 2 měsíci
New problem in this rabbit hole .... hihi
#198 YAESU SOMMERKAMP FT 221 Part 5
zhlédnutí 575Před 3 měsíci
Starting alignment - and again some PLL discussion
#197 YAESU SOMMERKAMP FT 221 Part 4
zhlédnutí 818Před 3 měsíci
Theorie of the PLL-Circuit and checking the Bias
#196 YAESU SOMMERKAMP FT 221 Part 3
zhlédnutí 651Před 4 měsíci
Suspicious behaviour - still a problem in the PLL-board?
#195 YAESU SOMMERKAMP FT 221 Part 2
zhlédnutí 630Před 5 měsíci
Struggling with undocumented mods, different versions of PLL and replacing RF-Pot.
#194 YAESU SOMMERKAMP FT 221 Part 1
zhlédnutí 974Před 5 měsíci
Oldie TRX from the 70ies; will we bring it back to life?
#193 Kenwood TS 450S
zhlédnutí 1,5KPřed 5 měsíci
Chasing birdies? What can we do - Or: Can we do anything or nothing?
#192 R&S EK070 Part 3(3)
zhlédnutí 1KPřed 7 měsíci
Overall tests of all electrolytics Part 1: czcams.com/video/fAAQB-KkVhQ/video.html Part 2: czcams.com/video/CkvC8SoSU6Y/video.html Part 3: czcams.com/video/75hAEIBehXA/video.html
#191 R&S EK070 Part 2(3)
zhlédnutí 850Před 8 měsíci
Swapping electrolytic caps in the power supply. Part 1: czcams.com/video/fAAQB-KkVhQ/video.html Part 2: czcams.com/video/CkvC8SoSU6Y/video.html Part 3: czcams.com/video/75hAEIBehXA/video.html
#190 R&S EK070 Part 1(3)
zhlédnutí 1,5KPřed 8 měsíci
Professional shortwave receiver with some problems in the power supply - and some explanations, demonstration and tests. Part 1: czcams.com/video/fAAQB-KkVhQ/video.html Part 2: czcams.com/video/CkvC8SoSU6Y/video.html Part 3: czcams.com/video/75hAEIBehXA/video.html
#189 AEG E800
zhlédnutí 1,7KPřed 8 měsíci
Professional shortwave receiver - no repair necessary! Only some explanations, demonstration and tests.
#188 Accord Peggie
zhlédnutí 584Před 8 měsíci
Little fully transistorized AM-Radio, which was on the german market in 1957! second.wiki/wiki/akkord-radio www.anode.de/wiki/index.php/Akkord_Peggie www.welt-der-alten-radios.de/ausstellung-transistorradios-1-1249.html
#187 MUSICAL FIDELITY A100-X Part 3(3)
zhlédnutí 970Před 9 měsíci
Other Repairs and Measurements with Bode plot and THD. Some chat. Part 1: czcams.com/video/NqwFCp2sMpM/video.html Part 2: czcams.com/video/2T1_5D8uMbM/video.html Part 3: czcams.com/video/P148zI0jaIg/video.html
#186 MUSICAL FIDELITY A100-X Part 2(3)
zhlédnutí 1,1KPřed 9 měsíci
#186 MUSICAL FIDELITY A100-X Part 2(3)
#185 MUSICAL FIDELITY A100-X Part 1(3)
zhlédnutí 2KPřed 9 měsíci
#185 MUSICAL FIDELITY A100-X Part 1(3)
I was thinking about terminator 1000. "That's it you're dead!"
So many capacitors, I am definitely not looking forward to it. Thank you for sharing! 73, KD2TDE
Caps, especially liquid types, are suspicious after many decades
@@dl7majstefan753 Oh I'm very well aware. I'll try to save the big filter caps since those are expensive, but everything else is suspect, and I'm thinking about changing them all out before I even plug it in. CDE makes a direct replacement for those RIFA RC networks, but polyester and dipped, so they should last, but they're expensive so I'll probably do what you did.
That's an interesting problem. I recently got one of these (mine does not have an A at the end) and the positive half of the sine wave seems to be clipped a bit. I am going to look into it so I appreciate you recording this video!
"Sounds of Mungo Jerry in the background, very relaxing." You are droll! Amazing restoration, great creativity.
Wo bekommt man denn eine Ersatzbatterie für das PLB1 her?
Ich versuche ja immer gerne zu helfen, wenn aber erkennbar selbst einfache Techniken des 21.Jahrhunderts (Suchmaschinen) Probleme verursachen, ist meine Geduld erschöpft - Sorry!!! Ich bin keine verlängerte Suchmaschine und kein Backoffice. Yachthandel - bevorzugt an der Küste; das wars dann!
@@dl7majstefan753 : wenn es so einfach wäre, dem Anfrager Dummheit oder Faulheit vorwerfen zu können, dann wäre eine Empörung auch angebracht. Dies ist jedoch in meinem Fall nicht der Fall! Ich habe intensiv nach einer Ersatzbatterie für mein PLB1 gesucht und auch ein Angebot für diese Ersatzbatterie gefunden. Jedoch wurde eine Auftragsannahme verweigert. Es würde nur in Verbindung mit einem Service-Auftrag geliefert: Hier die Korrespondenz dazu. "der von Ihnen angefragte Artikel „Ersatzbatterie-Kit LB7P für PLB1“ ist nur im Rahmen einer Batteriewechsels/Wartung Ihrer PLB1 erhältlich und nicht über unseren Webshop bestellbar. Das Ablaufdatum der aktuell im Zuge des Batteriewechsels von uns verbauten Batterien ist Januar 2032. Den Batteriewechsel für Ihre PLB bieten wir wie folgt an: Ersatzbatterie-Kit LB7P für PLB1 79,00 Euro Wartung Ocean Signal - PLB1 72,00 Euro Versandkosten (Rückversand) per Deutsche Post AG (DHL) 7,00 Euro Gesamtbetrag 158,00 Euro Die Durchlaufzeit für die Wartung beträgt zwei bis drei Tage. Wenn Sie unser Angebot annehmen möchten, senden Sie Ihr Gerät bitte an unsere nachstehende Anschrift On Yacht GmbH" Nun meine Frage an den erbosten Verfasser oder auch an andere Leser: Wo kann ich NUR die Ersatzbatterie, OHNE Einbau-Service beziehen? Alle meine Recherchen blieben bis dato erfolglos! Vielen Dank im Voraus!
Good job. Enjoyed the 260 cap tests.
After replacing the battery, you should use the test procedure to make sure everything is ok. One more question: where to find the replacement gasket?
It is shown and mentioned in the vid that the gasket is part of the new battery set. And of course the test procedure has to be executed.
@@dl7majstefan753 Thank you
Great work Stefan. I did not know the probe loop trick so thank you. From hot Tempe, AZ USA
Tnx also
This was drilled into us at Motorola and Kenwood to RTFM and understanding how the radio works and how to enter proper alignment modes. I went to another shop after the one I worked at closed down and was appalled at the bench tech as to how he aligned the Motorola Maxtrac and Radius line of radios that were popular some 20 plus years ago! Instead of using the computer with alignment software to set up the radio after a major repair he would just twiddle the caps and coils until the radio worked. Now the radio would come back time and time again for alignment issues. I was the low ball man on the bottom of the totem pole so I kept to myself. This was not the way to align these radios! Software controlled radios are a different beast compared to legacy Motorola and GE radios that had zero microprocessors in them. Funny I had fifteen years experience on these micro controlled radios and could have solved the problem in about an hour and a half of realignment by the book.
Thank you for the wonderful advice. I almost switched the speakers to my primary pair after running the hot amp for 5 days, few hours each day. Didnt realise on the lack of internal protection system eventhough i opened the cover to visually inspect the parts. What a great series, enjoyed every second of it. Thank you for taking the initiative and putting in much effort to share it with everyone. You probably saved my speakers that I intended to run the amp with.
Hi Stefan, excellent result after an arduous search for the root problem. I also have a Yaesu FT 857, I opened it and removed it (the conductive heatsink) Greetings from Chile CA5JXT Jaime 73.
Tnx dr Jaime
Something about KENWOOD that just gets my attention. Is it live, or is it Memorex? I mean KENWOOD!
Contrary to the manual can be best, I agree with vertical alignment. Also the accuracy comments in the manual are stupid. It's more accurate in the first half of the scale, not over the whole scale. Manual says use the most scale you can, if you check it, that's wrong so you are correct to think and not blindly follow the manual. Weather stripping for the battery it GREAT. Keep up the good work.
Great videos Stefan, from Tempe AZ
Tnx!
Hi Stefan. Pardon me for saying you look a little tired after this fix. Thing is, this is the true satisfaction of using you educated skills to repair a broken instrument. Take a break now, collect your wit, and forget about the battle for awhile. Cheers from West USA.
Tired? Maybe but the reason is not this project
thanks for sharing this very valuable video I can use it for my R4B
55 and best success
Manmanman Stefan, da hat man Dir aber wirklich ein faules Ei ins Nest gelegt ! Ich bewundere Deine Ausdauer, manch einer hätte das Gerät schon längst über den Jordan geworfen und wär zum nächsten Funkhändler gefahren, um sich was schickes neues zu kaufen. Die Herausforderung, das Ding zum Laufen zu bringen zeichnet Dich aber als wahren Funkamateur aus. Eigentlich hätte man das Gerät einem angehenden Funkamateur in die Hand drücken müssen, um sich im Technikverständnis zu beweisen. Es gibt kaum ein besseres Anschauungsobjekt wie diesen faulty TXRX der zeigt, was für HF- Fallstricke einen überraschen können. Drück Dir die Daumen, dass der FT221 Reparaturbericht im einstelligen Bereich bleibt (obwohl es ja immer spannend ist, Dir bei der Arbeit zuzuschauen 😉) 73, bleib gesund von DL1LAJ Andreas
Ja, Andreas; mehrmals wollte ich das Ding schon in die Tonne treten - aber dann hat doch mein Ehrgeiz gewonnen.
What an unusual problem, transformer failure is way down my list of suspects. Guess you got lucky (???) I have not seen that glue used on transformer windings but have seen plenty of damaged components and PCBs. Hopefully the alignment resolves all PLL issues - looking forward to part 9 and beyond 😀. Regards, David
That´s why i assumed a faulty uA703 and "never" thought about the transformer
that corrosive glue killed more transceivers than operator error. The solvent dries out, becomes porous, absorbs moisture, and eats away the insulations, even the legs of the components. It's a well known problem in Yaesu and Kenwood transceivers made in the 70-es and 80-es.
Yes, seems so. The enamel of the wires feels a little bit sticky and brittle.
Thank you for a great video. I follow.
Good morning Stefan, I live in London, I have a Yaesu FT-101Z, would | be able to send it there for a complete inspection and alignment...
Dear Jose, sri but my time is very limted and other projects are in the pipe. So i can´t accept new projects.
Good morning Stefan, I live in London, I have a Yaesu FT-101Z, would | be able to send it there for a complete inspection and alignment...
Hi good afternoon, :This is KC2DPY. I have the same tuner but when my radio has the preamp on its do not tune,any suggestions.
Sorry, no idea what the preamp has to do with the tuner. Maybe a problem with the antenna- and preamp relays?
Hello Stefan, I can't wait to see your discrete version of the uA703. Mit freundlichen grüßen
Hello Stefan, I sent you an e-mail with a suggestion! 73, Michele IZ2EAS
Tnx dr Michele, received and answered
Hopefully this will become a "Independence Day" movie equivalent with a little more troubleshooting and work! 73 - Dino KLØS
It is on a good track - project will be finalised (successful)
Great to see inside. I wonder how much knowledge the authorised batrery changers have and how much care they take in the procedure? In the uk at least its relatively recent that land use was licenced for such devices. Reading the opinions of prospective users or even rescue personnel is somewhat revealing. Ignorance is a remarkable thing. Why do replacmet batteries cost almost as much as a new device ? Even sealed bolt on batteries that are user changable. I think i'd rather have one of these that i had check myself than not have one at all for want of not being able to afford one. It is also legal to use unlike keying up on an aircraft frequency to get help in a remote catastrophe, or whatever other solution you can think of. Also I'm not going to accept some nonsense of.. if you can't afford £10/£100/£1000 per month for the subscription you shouldn't be doing it. Sarsat is global and open for any register user. It saves rescue teams hours or days and is surely the most accessible and efficient distress system going for remote and inaccessible areas. Why is the cost of safety so high? If you need to say because accidents cost more you clearly don't get the premise of a PLB. Every year we are battered with news reports of lost(missing) hikers in Scotland. Deliberate generation of a public hate for people "having to be rescued that shouldn't be there" What a difference it would make if these were accepted as commonplace here. It reads as though responsibility is not permitted here. The government and your peers don't allow it. You couldn't be responsible for not activating the life at risk device at any other time, and you certainly couldn't be responsible for changing the battery in such a thing. A great video. Informative. Interesting. Contentious!
Mni tnx. Agree with your comments
Hello Stefan, I se you have a HP counter is it a 5340A, i have a 5340A working so if you need to service your sometime you know where another is, if you need any measured values.
Tnx dr Peter, hope that it will be not necessary! Have enough problems here .... hihi.
Hallo, The Japanese modern substitute for uA703 is TA7060P but in SIL package in my country "IRAN" is very chip. good luck sir.
Tnx for the hint
you can use an MC1350 to amplify that signal, in case of absolute necessity. It has the advantage that its gain can be set with an external resistor, and the IC is really cheap.
Tnx for the hint
Hallo Stefan, den LM703 habe ich damals nach dem Vorschlag von DL4CS nachgebaut. Aber sicher hast Du seinen Vorschlag schon beim Googeln gefunden. 73 Bernd
Hallo Bernd, Danke für den Tip. Habe inzwischen den NE592 entdeckt - der ist für unter 1,- verfügbar.
@@dl7majstefan753 Ah, interessant.....da bin ich auf das nächste Video gespannt👍👍👍
A very funny movie to watch, but not so funny to live! I checked my bench stock, but no 703s to be found. You might look at the TI THS4130 or THS4131 as a substitute (with a small adapter board), around $8 US from Mouser or at your favorite supplier. Regards, David
Tnx, i´ve found meanwhile the NE592, which is also rather cheap.
Maybe you can buy it from svebry electronics in sweden only 20sek
Deutschland schafft sich ab.......... Schwätz DEUTSCH !!!
Is that a switching power supply?
It is explained in detail in part 2
At this point japanese consumer grade receivers surpas american professional grade receivers in terms of quality and longevity. 😂
Hoe about putting a proper transformer with diodebridge stabilizer transistor and big elco's and throw that switching source in the bin instead of servicing it
Switching power source 🤢
Never ending work is never easy. 😉
I noticed it only had 2 pins on the power plug in the 1st video and wasnt impressed, Ive never seen that before, I think I would change that. Very good thorough analysis. I have to say in my experience those old Philips caps in the smaller sizes are generally bad but you are quite right its getting harder to get axial replacements.
Many Philips Equipments have only two pins; the case is therefore isolated and not grounded! That´s made intentionally to avoid ground loops but requires some considerations in the measurement arrangement. Isolation of the scope is good enough (safety class II, double insulated)
@@dl7majstefan753 Ive not seen that in New Zealand, perhaps local regulations forced this to be changed before import. I'm not sure how a scope can be double insulated if the metal case can become live?
@@campbellmorrison8540 The metal case is painted and there are ground connections on the front, which have to be grounded before use! The double isolation is referred to the primary wiring and transformer isolation. That´s all i know.
You're awesome, Stefan.
Tnx
Manmanman, nimmt ja kein Ende mit dem FT221, Stefan. Man könnte meinen, FT steht für Fehlerteufel ;-) Zum Glück sind die Bauteile nicht noch mit irgendwelchen Klebern befestigt, der sie irgendwann mal durch Zersetzen angreift. 73, beste Gesundheit von Andreas, DL1LAJ
Tnx Andreas, ja, zum Glück gibt es hier diese Kleber nicht! Die Elkos scheinen auch nur gelötet, nicht geklebt - hab aber noch nicht alle visuell inspiziert. Drück mir die Daumen....hi.
I wonder if over time with the output set so high that the diode was stressed providing the ALC and that's why it failed, although that theory is a stretch. OR it was just the diode's time to go! ;-) Look forward to Part 7, have a great weekend Stefan! 73 - Dino KLØS
I don´t think, that the diode was killed by high output. Even with high output, the ALC-voltage is not more than some volts - just sufficient to control two depletion type FETs in the SSB-chain. The most endangered diode ist the germanium diode just behind the capacitive divider from the output; could be killed by transisnts during RX/TX switching. But this diode is OK!
Hey Stefan, I see that the saga continues. It's amazing how many little things you can find wrong with a rig like that. Looking forward to your next video. Stay healthy my friend.
Tnx dr Joe
It's crazy how many errors accumulate over time. In addition to all the age-related errors in the components, there are also those of the golden screwdriver heroes and "ingenious" modifiers ;-) But you exposes them all.👍 It was very interesting to watch your work. mny tnx es 73 de Bernd
Ja Bernd! wenn der TRX doch nur reden könnte - er hätte bestimmt viel zu erzählen! Hihi
@@dl7majstefan753 ... dann könnte man ihm schneller helfen.
Nice Rig Stefan, when i was getting my ham license early 80´s the Yeasu FT-101ZD was introduced LED frequency was very cool back then. Bye the way all mail i tried to send you bunced back after a week non deliverable. 🙃
dl7maj@t-online.de will work - i checked it!!! If not pse send me your mail-address - i will respond!
@@dl7majstefan753 Sent a testmail now
Thanks very much. You helped me out quite a bit!⭐
Hallo Stefan, danke für dieses Video, man findet leider nicht so viel über dieses Gerät.
Ja, im deutschsprachigen Raum eher unbekannt.
Thankyou very much Stefan. I see you went through much pain to achieve the final result. I know this pain working on older test equipment. I am once again a FT221R owner (for fun on 2m like old days...). Thankyou for sharing your hard won efforts. Excellent video's...73 de M0BTZ
Mni tnx dr OM
Hi Stefan, you amaze me with your tenacity in tracking down the problem. Great job!!!
Mni tnx dr Joe!